To provide passengers with additional in-flight comfort, newer aircraft seating systems are more adjustable than conventional seating systems and may allow passengers to, among other things, laterally (e.g., fore and aft) translate a seat substructure (i.e., seating surface including a seatback and seatbase) relative to a base substructure that is attached to a floor of the aircraft. However, until now, such aircraft seating systems have presented a challenge with respect to preventing the moveable seat substructures from becoming disconnected from the fixed stationary base substructure during a dynamic event such as may be experienced by an aircraft during an aborted takeoff or crash landing.
Inertia latch mechanisms are known in the automotive industry for preventing forward seat movement and seatback folding during a rapid deceleration of the automotive vehicle. Examples of such mechanisms can be found in U.S. Pat. Nos. 4,294,488 (Pickles) and 4,988,134 (Vidwans et al.). While these mechanisms utilize latching devices, including pendulum-type latches that respond to a predetermined deceleration, they do not have a locking mechanism that positively locks them into place once they have been engaged. As a result, these latch mechanisms may suffer from bounce-back or vibration and become disengaged.
One inertia lock apparatus that overcomes the foregoing-described problems is shown in FIGS. 1, 2A and 2B. Referring to FIG. 1, the inertia lock apparatus 100′ is configured inside the seating system 200′ with a pendulum latch 120′ of inertia lock apparatus 100′ being coupled to the base substructure 220′, which is stationary, and a striker bar 230′ being connected to the seat substructure 240′, which is at least laterally moveable forward and backward above the base substructure 220′ as indicated by the double-headed arrow labeled with “Front” and “Back.”
The base substructure 220′ of vehicle seating system 200′ includes a left base rail 222l′ (not shown), a right base rail 222r′, an intermediate base rail 222i′, a front tubular member 224′ and a rear tubular member 226′. As can be appreciated, the left, right and intermediate base rails 222l′, 222r′, 222i′ are spaced apart from each other and generally parallel to each other, extending generally parallel with the right and left sides of the seatbase (250, FIG. 4). Furthermore, the front and rear tubular members 224′, 226′ are spaced apart and generally parallel to each other, extending generally parallel with the front and rear sides of the seatbase (250, FIG. 4). The front and rear tubular members 224′, 226′ couple with the left, right and intermediate base rails 222l′, 222r′, 222i′ to configure the base substructure 220′ as a generally rectangular, rigid frame.
Although not illustrated in FIG. 1, one can appreciate that the seat substructure 240′ may be substantially similar to seat substructure 240 (FIG. 4) and include a seatbase (250, FIG. 4), a seatback (260, FIG. 4) that may be pivotally coupled to a rear portion of the seatbase and configured to recline from a generally vertical orientation, a legrest (270, FIG. 4) that may be pivotally coupled to a front portion of the seatbase and configured to raise and lower, and left and right armrests (280, 280′, FIG. 4) that may be coupled to right and left sides of the seatbase. As illustrated in FIG. 1, the inertia lock apparatus 100′ is provided on the right side of the example vehicle seating system 200′. However, the inertia lock apparatus 100′ may alternatively be provided on the left side of the example vehicle seating system 200′. Furthermore, it should be appreciated that the example vehicle seating system 200′ may include additional inertia lock apparatuses, for example, a left side inertia lock apparatus and a right side inertia lock apparatus.
As described previously, the seat substructure 240′ is configured to laterally move forward and rearward above the base substructure 220′. To this end, the seat substructure 240′ as shown includes on its bottom surface a gear rack 242′ or the like having a plurality of teeth 244′. Further, the stationary base substructure 220′ includes at its front side a spur gear 228′ that is rotatably coupled with the axle of a rotary actuator 232. The spur gear 228′ meshes with the plurality of teeth 244′ of the gear rack 242′ so that the seat substructure 240′ moves when the actuator 232 is activated.
As further shown in FIG. 1, the inertia lock apparatus 100′ is connected to the vehicle seating system 200′ proximate a bottom portion of the seat substructure 240′ such that, when the seat substructure 240′ is oriented in a TTL (i.e., taxi, takeoff, and landing position wherein the seatback is substantially upright and the seat substructure 240′ is not translated substantially forward or rearward relative to the base substructure 220′), the inertia lock apparatus 100′ is substantially proximate the striker bar 230′. As can be appreciated, the inertia lock apparatus 100′ provides a failsafe to catch the striker bar 230′ which may move forwardly with the seat substructure 240′ during a dynamic event, thereby preventing the seat substructure 240′ from becoming uncoupled from the base substructure 220′ if one or more of the actuator 232, spur gear 228′ or gear rack 242′ were to fail, break or otherwise malfunction. Although the seat substructure 240′ is described as including the striker bar 230′ and the gear rack 242′, and the base substructure 220′ is described as including the spur gear 228′ and rotary actuator 232, the seat substructure 240′ and base substructure 220′ may be configured otherwise, for example, vice-versa such that the seat substructure 240′ includes the spur gear 228′ and rotary actuator 232′, and the base substructure 220′ includes striker bar 230′ and the gear rack 242′. Furthermore, other mechanism and devices, for example, linear actuators, that are known in the art may be suitably employed additionally with or alternatively to the foregoing for moving the seat substructure 240′ relative to the base substructure 220′.
Referring now to FIGS. 2A and 2B, the inertia lock apparatus 100′ of FIG. 1 is further illustrated and the operation thereof will be described in further detail. As shown in FIG. 2A, the inertia lock apparatus 100′ includes a pendulum latch 120′ and a lock mechanism 160′. The pendulum latch 120′ may machined, cast or the like of a suitable material such as metal (e.g., steel, aluminum, etc.) and is elongate along the forward-rearward direction. The pendulum latch 120′ as illustrated includes a forward end 102′ with a catch portion 140′ and a rearward end 104′ with a mass portion 130′. As shown, the mass portion 130′ and catch portion 140′ may be unitarily formed (e.g., cast, machined, molded or the like) such that the pendulum latch 120′ is one-piece. As shown, the catch portion 140′ includes a hook 142′ that extends generally upward and rearward from a bottom portion of the forward end 102′, providing a generally U-shaped channel 144′ that is configured to align with the striker bar 230′ as best illustrated in FIG. 2B for catching thereon.
The pendulum latch 120′ is pivotally attached to the base substructure 220′ at pivot point 150′ that is configured at a top portion of the pendulum latch 120′ intermediate the forward end 102′ and the rearward end 104′. The pivot point 150′ may be a fastener such as a screw, bolt, rod, pin or the like that is extended through an aperture of the pendulum latch 120′ and attached to the base substructure 220′. As shown in FIG. 2A, the mass portion 130′ and the pivot point 150′ are configured so that the catch portion 140′ of the pendulum latch 120′ is normally oriented to be lower than the striker bar 230 (i.e., the normal orientation or state of the pendulum latch 120′) so that the seat substructure 240′ may be moved forward and rearward in an unimpeded manner during normal in-flight conditions. Furthermore, the pendulum latch 120′ is configured so that the pendulum latch 120′ rotates clockwise about the pivot point 150′ only during a dynamic event having a predetermined force or acceleration. More particularly, the mass portion 130′ and the pivot point 150′ are configured to cooperate such that the mass portion 130′ will rotate downward and forward (as indicated in FIG. 2A by the curved arrow labeled “R′”) when the vehicle experiences a predetermined deceleration in the range of about 6 G-9 G (i.e., six to nine multiples of the acceleration due to gravitational force −9.8 meters/second2). As best illustrated in FIG. 2B, once the vehicle has experienced the predetermined deceleration, the pendulum latch 120′ is shown in its latching orientation or state wherein the catch portion 140′ is positively aligned and maintained in that orientation or state to catch the striker bar 230′. In this way, the seat substructure 240′ is prevented from potentially becoming decoupled from the base substructure 220′ during a dynamic event.
Referring to FIGS. 2A and 2B, the lock mechanism 160′ of inertia lock apparatus 100′ is described. As shown in FIG. 2A, the lock mechanism 160′ includes a pawl member 162′ configured generally forward and downward or lower relative to the pivot point 150′. As shown, the pawl member 162′ may be a fastener such as a screw, bolt, rod, pin or the like that is connected to the right base rail 222r′ and which extends through an aperture 122′ (having a sideways L-shape) of the pendulum latch 120′ and past the left-hand or inward-facing surface of the pendulum latch 120′. As shown in FIG. 2A, the pawl member 162′ is oriented generally forward in the aperture 122′ when the pendulum latch 120′ is in its normal orientation or state. As shown in FIG. 2B, the pawl member 162′ is oriented generally rearward in the aperture 122′ when the pendulum latch 120′ is in its latching orientation or state (i.e., after rotating clockwise on the pivot point 150′ due to an occurrence of a dynamic event, for example).
A stop member 170′ is configured proximate the aperture 122′ and the pawl member 162′ to obviate, inhibit or otherwise prevent the pendulum latch 120′ from becoming misaligned (i.e., rotating in a clockwise direction) with the striker bar 230′ after the pendulum latch 120′ has moved to its latching orientation or state. As shown, the stop member 170′ is pivotally coupled to the pendulum latch 120′ by lock pivot point 172′ below the aperture 122′ and intermediate the rearward and forward ends 124′, 126′ of the aperture 122′. The stop member 170′ as shown includes a generally triangular-shaped body with an upper corner or shoulder 174′, a lower corner or shoulder 176′ and a forward corner or shoulder 178′. The stop member 170′ is biased such that upper shoulder 174′ is configured to normally extend above the lower surface 128′ of aperture 122′.
As shown, lower shoulder 176′ is coupled to one end of an extension spring 182′, the other end of which is coupled to an anchor portion 146′ of the pendulum latch 120′ proximate the mass portion 130′. Although the bias for stop member 170′ is provided by the extension spring 182′ as shown, the bias may be provided by other springs such as a torsion spring, a compression spring or by other biasing and elastic members or devices known in the art. As can be appreciated, the extension spring 182′ has a tension to provide a counterclockwise rotational bias that normally urges the rearward edge (i.e., the edge extending between the upper shoulder 174′ and lower shoulder 176′) of stop member 170′ against a stop 180′ (e.g., a fastener as shown). Thus configured, as the pendulum latch 120′ rotates in a clockwise manner, the aperture 122′ moves generally forward and upward so that the pawl member 162′ contacts the upper shoulder 174′ thereby causing the stop member 170′ to pivot clockwise about lock pivot point 172′. As the stop member 170′ is moved forward (i.e., by further pivoting of the pendulum latch 120′) past the pawl member 162′, the spring 182′ provides a restoring force to pivot the stop member 170′ counterclockwise such that upper shoulder 174′ again extends above the lower surface 128′ of aperture 122′. As shown in FIG. 2B, once the stop member 170′ has traveled forward past the pawl member 162′, the stop member 170′ (particularly the upper shoulder 174′) interferes with the pawl member 162′ to provide a positive stop that obviates, inhibits or otherwise prevents the pendulum latch 120′ from rotating counterclockwise and moving from the latching orientation or state to the normal orientation or state. In this way, the inertia lock apparatus 100′ is configured to resist bounce-back (e.g., due to impact loads), thereby ensuring positive latching and substantially irreversible securing of the seat substructure 240′ to the base substructure 220′.
The foregoing-described inertia lock apparatus may be advantageously employed for various seating systems. However, further refinements to the apparatus would be important developments in the art.